ECG triggered heart and arterial magnetic resonance imaging

Abstract

High resistance non-metallic ECG leads are used to capture biologically generated electrical signals, and include at least one magnetic resonance noise lead to capture a noise reference signal indicative of electromagnetic noise ambient to the leads generated by magnetic resonance imaging (MRI). The noise reference signal is canceled from the captured electrical signal using an adaptive canceling noise filter to obtain a processed electrical signal indicative of the biologically generated electrical signal that causes movement in a patient's moving body part, such as the heart. A characteristic of the processing electrical signal indicative of the biologically generated electrical signal that causes the movement is detected to obtain a trigger signal, which is then transmitted to cause the MRI system to capture at least one imagine including the moving body part.

We claim: 
     
       1. A method for triggering a magnetic resonance imaging system, comprising:
 capturing a noisy electrical signal, via at least one main lead, including a biologically generated electrical signal that causes movement in a moving body part of a living being, and noise; 
 capturing, via at least one magnetic resonance noise lead, a noise reference signal indicative of magnetic resonance electromagnetic noise ambient to the at least one main lead; 
 receiving, by a receiving device, the captured noisy electrical signal and the noise reference signal; 
 canceling, by a processing device, the noise reference signal from the captured electrical signal to obtain a processed electrical signal indicative of the biologically generated electrical signal that causes movement in the moving body part of the living being using an adaptive canceling noise filter; 
 detecting, by a processing device, a characteristic of the processed electrical signal indicative of the biologically generated electrical signal that causes movement in the moving body part of the living being to obtain a trigger signal; and 
 transmitting, by a transmitting device, the trigger signal to cause the magnetic resonance imaging system to capture at least one image including the moving body part of a living being. 
 
     
     
       2. The method of  claim 1 , wherein the moving body part is at least one of a heart, blood vessel, and cardiovascular system. 
     
     
       3. The method of  claim 1 , wherein the moving body part is a heart of a human subject and the at least one main lead is located on the chest of the human subject. 
     
     
       4. The method of  claim 1 , wherein the moving body part is a heart of a human subject and the at least one magnetic resonance noise lead is located on at least one of an arm or a leg of the human subject. 
     
     
       5. The method of  claim 1 , wherein the at least one main lead and the at least one magnetic resonance noise lead include carbon filament wires without metallic inclusions. 
     
     
       6. The method of  claim 1 , wherein the adaptive canceling noise filter is at least one of: a least mean square filter, a recursive least square filter, and a least square lattice filter. 
     
     
       7. The method of  claim 1 , further comprising:
 identifying, by the processing device, a vector statistic based on the processed electrical signal using a Gram-Schmidt Orthogonalization algorithm, wherein the trigger signal transmitted to the magnetic resonance imaging system is the identified vector statistic. 
 
     
     
       8. A system for triggering a magnetic resonance imaging system, comprising:
 at least one main lead configured to capture a noisy electrical signal including a biologically generated electrical signal that causes movement in a moving body part of a living being, and noise; 
 at least one magnetic resonance noise lead configured to capture a noise reference signal indicative of magnetic resonance gradient electromagnetic noise ambient to the at least one main lead; 
 a receiving device configured to receive the captured noisy electrical signal and the noise reference signal; 
 a processing device configured to cancel the noise reference signal from the captured noisy electrical signal to obtain a processed electrical signal indicative of the electrical signal that causes movement in the moving body part of the living being using an adaptive canceling noise filter and configured to detect a characteristic of the processed electrical signal to obtain a trigger signal; and 
 a transmitting device configured to transmit the trigger signal to a magnetic resonance imaging system to cause the magnetic resonance imaging system to capture at least one image including the moving body part of the living body. 
 
     
     
       9. The system of  claim 8 , wherein the moving body part of a living being is at least one of a heart, blood vessel, and cardiovascular system. 
     
     
       10. The system of  claim 8 , wherein the moving body part of a living being is a heart of a human subject and the at least one main lead is adapted to be located on the chest of the human subject. 
     
     
       11. The system of  claim 8 , wherein the moving body part of a living being is a heart of a human subject and the at least one magnetic resonance noise lead is adapted to be located on at least one of an arm or a leg of the human subject. 
     
     
       12. The system of  claim 8 , wherein the at least one main lead and the at least one magnetic resonance noise lead include carbon filament wires without metallic inclusions. 
     
     
       13. The system of  claim 8 , wherein the adaptive canceling noise filter is at least one of: a least mean square filter, a recursive least square filter, and a least square lattice filter. 
     
     
       14. The system of  claim 8 , wherein
 the processing device is further configured to identify a vector statistic based on the processed electrical signal using a Gram-Schmidt Orthogonalization algorithm, wherein the trigger signal transmitted to the magnetic resonance imaging system is the identified vector statistic.